They did away with it and I think it was a mistake. Specialization is a good thing.
Can expand it to include something like Industrial-specialized slots too.
What I'd like to see are specialized modules to go with specialized slots, that give bonuses beyond their non-specialized counterparts. That way you can still use a ship for any role but if it utilizes it's specialized slots it's that much better and that much more attractive for that role. This is not a thought-out idea so no examples of what I mean, but say a specialized refinery module for an Industrial-only slot could hold more or operate faster, specialized passenger modules might offer more seats or more comfort for a pay boost (or something like that), trade-only cargo racks maybe give a weight reduction or who knows...
This !!! Perfect !